﻿using System;
using System.Collections.Generic;
using System.Text;
using System.Xml.Serialization;
using System.Runtime.Serialization;

namespace HtmlSanitizer
{
    [XmlRoot("Dictionary")]
    public class XmlSerializableDictionary<TKey, TValue> 
        : Dictionary<TKey, TValue>, IXmlSerializable
    {
        #region Private Constants
        private const string ITEM = "Item";
        private const string KEY = "Key";
        private const string VALUE = "Value";
        #endregion

        #region Constructors
        public XmlSerializableDictionary()
            : base()
        {
        }
        public XmlSerializableDictionary(IDictionary<TKey, TValue> dictionary)
            : base(dictionary)
        {
        }
        public XmlSerializableDictionary(IEqualityComparer<TKey> comparer)
            : base(comparer)
        {
        }
        public XmlSerializableDictionary(int capacity)
            : base(capacity)
        {
        }
        public XmlSerializableDictionary(IDictionary<TKey, TValue> dictionary, IEqualityComparer<TKey> comparer)
            : base(dictionary, comparer)
        {
        }
        public XmlSerializableDictionary(int capacity, IEqualityComparer<TKey> comparer)
            : base(capacity, comparer)
        {
        }
        protected XmlSerializableDictionary(SerializationInfo info, StreamingContext context)
            : base(info, context)
        {
        }
        #endregion

        #region IXmlSerializable Members
        public System.Xml.Schema.XmlSchema GetSchema()
        {
            return null;
        }

        public void ReadXml(System.Xml.XmlReader reader)
        {
            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));

            bool wasEmpty = reader.IsEmptyElement;
            reader.Read();

            if (wasEmpty)
                return;

            while (reader.NodeType != System.Xml.XmlNodeType.EndElement)
            {
                reader.ReadStartElement(ITEM);

                reader.ReadStartElement(KEY);
                TKey key = (TKey)keySerializer.Deserialize(reader);
                reader.ReadEndElement();

                reader.ReadStartElement(VALUE);
                TValue value = (TValue)valueSerializer.Deserialize(reader);
                reader.ReadEndElement();

                this.Add(key, value);
                reader.ReadEndElement();
                reader.MoveToContent();
            }
            reader.ReadEndElement();
        }

        public void WriteXml(System.Xml.XmlWriter writer)
        {
            XmlSerializer keySerializer = new XmlSerializer(typeof(TKey));
            XmlSerializer valueSerializer = new XmlSerializer(typeof(TValue));
            foreach (TKey key in this.Keys)
            {
                writer.WriteStartElement(ITEM);
                writer.WriteStartElement(KEY);
                keySerializer.Serialize(writer, key);
                writer.WriteEndElement();
                writer.WriteStartElement(VALUE);
                TValue value = this[key];
                valueSerializer.Serialize(writer, value);
                writer.WriteEndElement();
                writer.WriteEndElement();
            }
        }
        #endregion
    }
}

